TiO2-CdSe nanowire arrays showing visible-range light absorption

High-density single crystalline TiO2 nanowires (similar to 50 nm diameter) were grown on Ti substrates by chemical vapor deposition, and they were overcoated with the solution containing CdSe nanocrystals (similar to 5 nm diameter) and heat treated at 600 degrees C to form TiO2 hetersotructured nanowire arrays. The TiO2 nanowire arrays showed uniformly distributed CdSe nanocrystals and high crystallinity of rutile and wurtzite from the TiO2 and the CdSe, respectively. Owing to the heterostructure of TiO2, they demonstrate almost full visible-range light absorption, and thus enhanced photocatalytic activity by the charge separation via electron and hole transfers between the CdSe and the TiO2.